This invention relates generally to a connector for electrical cables and more particularly to a leak-tight connector for use in the wall of a housing containing electrical components submerged in a fluid as in a hydraulic control system of an automatic transmission.
In a hydraulic control system of an automatic transmission, an electrical device which operates while immersed in fluid, such as a solenoid valve, is installed in a housing of the hydraulic control system, and an electronic control system which generates a control signal for the electrical device is provided outside of the housing.
To prevent the fluid used in the hydraulic control system from leaking through, that is, along the electrical cable or cables which connect between the electric device in the housing and the electronic control system outside of the housing, a sealing device including a rubber bushing is fitted in a hole formed in the housing. The cable or cables are inserted through the rubber bushing, and then are drawn out to the exterior from the inside of the housing while relying on the rubber bushing for prevention of leakage. However, such a conventional sealing device has many drawbacks as follows.
The temperature of the fluid used in a hydraulic control system of an automatic transmission becomes very high during operation of the automatic transmission. Therefore, a cable or cables are used which consist of a bundle of electric wires coated cylindrically over the outer periphery with tetrafluoroethylene, which is known under the trademark Teflon. Such a coated cable is referred to hereinafter as Teflon cable.
However, Teflon cable is expensive so when Teflon cable is used for the portion of the cable on the external side of the housing, the cost is increased. In such a construction, moreover, because a single Teflon cable connects between the interior and exterior of the housing, the fluid in the housing leaks to the exterior of the housing due to capillarity through the clearance between the electric wires in the Teflon cable and the clearance between those wires and the cylindrical Teflon coating.
What is needed is a connector through a housing containing fluids in which electrical components are immersed, which is leak-tight, simple to install, and economical in application.